Highway work zone safety has been a concern nationwide and will likely draw ever increasing attention as more highway funds are being invested in the maintenance of existing highways. To improve work zone safety, the Indiana Department of Transportation (INDOT) established a special fund for work zone patrolling, and this study was commissioned to help INDOT achieve the maximum safety benefits within their budget constraint.

With help of INDOT, a survey of project engineers was conducted to collect work zone information. It has been linked with other available data. A Random Effect Negative Binomial model was developed to identify the contributing factors and to estimate crash frequency in highway work zones. The results from the model provided insight to better understand work zone crashes. Various factors, including roadway information, traffic volume, work zone specific features, and police presence were identified as affecting work zone crash frequency; and these and other findings will be used to plan police enforcement activities in future INDOT work zones.